An ink jet recording method can form an image simply and inexpensively and thus can be applied to various printing fields, for example, photography, various kinds of printing, and special printing such as marking and color filters. Recently, the ink jet recording method has also been used for printing on materials such as glass, resins, or metal. In this way, as not only paper but also other materials start to be used as a printing object, various methods have been developed, the methods including: a water-based ink jet method; a phase change ink jet method in which a solid wax ink is used at room temperature; a solvent-based ink jet method in which an ink containing a quick-drying organic solvent as a major component is used; and a UV ink jet method in which ultraviolet (UV) rays are used for crosslinking after recording.
In particular, the UV ink jet method is less malodorous than the solvent-based ink jet method, and with this method, an image can be formed on a recording medium having no quick-drying properties and no ink absorbency. Therefore, the UV ink jet method has been put into practice.
In the UV inkjet method, a radically curable material containing a (meth)acrylate material is mainly used. However, as compared to a radically curable material, a cationically curable material containing epoxy, vinyl ether, or oxetane has, for example, the following advantageous effects: (a) curing inhibition caused by oxygen is not likely to occur, and a thin film can be cured in the air; (b) the amount of shrinkage is small during curing, and adhesion is superior; and (c) even after curing by light irradiation, curing progresses due to a dark reaction (refer to Non-Patent Document 1). Therefore, recently, the cationically curable material has been increasingly applied to a coating material, an adhesive, a sealing agent for a display, a printing ink, three dimensional modeling, a silicone release paper, a photoresist, or a sealing agent for an electronic component.
In the ink jet printing field, for example, Patent Document 1 discloses an image forming method including: ejecting an active ray-curable ink, which contains a compound having an oxirane group and a compound having an oxetane ring as a photoacid generator and a photocationically polymerizable compound, from an inkjet recording head onto a recording material to print an image on the recording material. In this image forming method, after being landed on the recording material, the active ray-curable ink is cured with light having a wavelength of 210 nm to 280 nm. The image forming method is applicable to a non-absorbent recording material.
In addition, Patent Document 2 discloses a composition including: an epoxy group-containing silane coupling agent having both photocationic curability and silane coupling properties; and a photocationic polymerization initiator. According to the technique disclosed in Patent Document 2, it is possible to provide a photocationically curable composition that has superior adhesion with a substrate such as glass or a resin and is highly transparent after being cured; and a coating material and an ink for an ink jet printer that are formed of the composition.